Левит 27:18

The directions concerning vows follow the express termination of the Sinaitic lawgiving (Lev 26:46), as an appendix to it, because vows formed no integral part of the covenant laws, but were a freewill expression of piety common to almost all nations, and belonged to the modes of worship current in all religions, which were not demanded and might be omitted altogether, and which really lay outside the law, though it was necessary to bring them into harmony with the demands of the law upon Israel. Making a vow, therefore, or dedicating anything to the Lord by vowing, was not commanded, but was presupposed as a manifestation of reverence for God, sanctified by ancient tradition, and was simply regulated according to the principle laid down in Deu 23:22-24, that it was not a sin to refrain from vowing, but that every vow, when once it had been made, was to be conscientiously and inviolably kept (cf. Pro 20:25; Ecc 5:3-5), and the neglect to keep it to be atoned for with a sin-offering (Lev 5:4). - The objects of a vow might be persons (Lev 27:2-8), cattle (Lev 27:9-13), houses (Lev 27:14, Lev 27:15), and land (Lev 27:16-25), all of which might be redeemed with the exception of sacrificial animals; but not the first-born (Lev 27:26), nor persons and things dedicated to the Lord by the ban (Lev 27:28, Lev 27:29), nor tithes (Lev 27:30-33), because all of these were to be handed over to the Lord according to the law, and therefore could not be redeemed. This followed from the very idea of the vow. For a vow was a promise made by any one to dedicate and given his own person, or a portion of his property, to the Lord for averting some danger and distress, or for bringing to his possession some desired earthly good. - Besides ordinary vowing or promising to give, there was also…

The last verse of the foregoing chapter seemed to close up the statute-book; yet this chapter is added as an appendix. Having given laws concerning instituted services, here he directs concerning vows and voluntary services, the free-will offerings of their mouth. Perhaps some devout serious people among them might be so affected with what Moses had delivered to them in the foregoing chapter as in a pang of zeal to consecrate themselves, or their children, or estates to him: this, because honestly meant, God would accept; but, because men are apt to repent of such vows, he leaves room for the redemption of what had been so consecrated, at a certain rate. Here is, I. The law concerning what was sanctified to God, persons (Lev 27:2-8), cattle, clean or unclean (Lev 27:9-13), houses and lands (Lev 27:15-25), with an exception of firstlings, (Lev 27:26, Lev 27:27). II. Concerning what was devoted (Lev 27:28, Lev 27:29). III. Concerning tithes (Lev 27:30, etc.).